According to the Declaration of Independence, in the founding paragraph of America, the very reason for the existence of government is to protect the self-evident right to life.
"We hold these truths to be self-evident, that all men are created equal, that they are endowed by their Creator with certain unalienable Rights, that among these are Life, Liberty and the pursuit of Happiness. — That to secure these rights, Governments are instituted among Men..."
I am going to go ahead and assume you are not a Southerner, based on that comment. Slavery and abortion have absolutely nothing to do with each other. The only thing they have in common are that they are issues that are divisive and divide the country.
And this actually justifies my position. The reason we have a problem in this country is because legalized abortion is mandated upon all states whether or not the residents of the respective states actually want that. Mandating that abortion be illegal, irrespective of the desire of those states voters, csuses the exact same problems. And in your argument, you further my position that people in different parts of the country believe different things regarding the role of government, thereby making a national imperative improper.